The invention relates to a crankshaft seal for an internal combustion engine, comprising a die cast carrier with a lipped ring of polymeric material which is fastened to the carrier by means of a supporting piece formed of sheet metal.
Such a crankshaft seal for an internal combustion engine is disclosed in U.S. Pat. No. 4,484,751. A die cast cover has a dynamic sealing area and two static sealing areas, all three disposed in different planes. All three sealing areas lying in different planes have profiled rubber sealing elements, the sealing element for sealing the crankshaft being vulcanized onto a radial projection of the basic carrier body, while the other sealing elements, which are formed by rubber rectangular profiles, are fixed in milled grooves. This arrangement assures a precise fixation provided with uniform contact pressure on the adjacent part, but it is to be noted that, on account of the direct arrangement of the sealing elements in the cover results in an elevated cost of manufacture, so that the cover is not very satisfactory from an economic point of view. Furthermore, this arrangement is comparatively heavy.
A similar crankshaft seal is disclosed in U.S. Pat. No. 4,928,980. Accordingly, a cover for a casing has a dynamically acting seal for sealing a shaft and a statically acting seal for a cover flange surface, the cover consisting of a drawn sheet-metal body with a plurality of radial surfaces onto which the seals are vulcanized. However, it is to be noted that a plurality of fastening holes are to be provided at close intervals in order to produce a sufficiently great pressure of the sheet-metal cover an engine block. Furthermore, the thickness of the sheet metal body is comparatively great and it has numerous bends, making the body difficult to manufacture.